<template>
  <div>
    <button @click="onClick">点击，提交 mutation</button>
  </div>
</template>

<script>
// 引入 常量
import { CHANGE_A } from "@/store/mutation-types";

export default {
  methods: {
    onClick() {
      this.$store.commit(CHANGE_A, 200);
    },
  },
};
</script>
